A radio communication system generally consists of a terminal, an access service network and a content service network. The access service network plus the content service network can be called radio communication network, wherein the access service network comprises control stations (or base stations) and gateways. The radio communication network may be regarded as a set of equipments for providing services, and terminals or user equipments are equipments receiving services. The control stations in the radio communication network perform radio communication with terminals by electromagnetic waves. The radio communication network can provide radio coverage for terminals within a certain geographic range which is called a cell.
FIG. 1 is a diagram of a radio communication system according to related technologies. As shown in FIG. 1, the radio communication system comprises a terminal, a control station, a gateway and a content service network, wherein the control station and the gateway belong to the access service network. Both the access service network and the content service network belong to the radio communication network. “Terminal requests to access the network” means that the terminal requests to access (or connects to, or attaches to) the radio communication network, and communication between the terminal and the radio communication network is achieved by communication between the terminal and the control station. But processing of requests from the terminal may be done by different parts of the radio communication network. For example, it may be done by the control station, may be done by the gateway, and also may be done by the content service network (in which an Authentication, Authorization and Accounting (AAA) server is provided).
In the related technologies, terminals, for example, the mobile phones are corresponding to users one by one. That is, in the view of the radio communication network, one terminal is corresponding to one logic user. However, with the expansion of the application of the radio communication system to wider fields, various types of terminals (user equipments) can get services from the radio communication network. In these terminals, some terminals have multiple-to-one relations with users. That is, multiple terminals are corresponding to one user. For example, in the field of machine type communication (MTC, or machine to machine communications or Internet of Things), it is possible that several, dozens of or even more terminals belong to a same user.
Therefore, when the above multiple terminals access (or connect to, or attach to) the radio communication network, a huge non-data-service overhead may be caused to the radio communication network if the access of each terminal is implemented without differentiation.